Modular plugs, which are used to terminate retractile cords that connect a telephone base to a handset, provide a customer as well as an installer with the capability of easily changing cords by removing the plugs from jacks in the base and handset and then reinstalling a new or refurbished cord. Newly obtained telephones are easily connected to existing wall terminals by inserting a modular plug which terminates one end of a line cord into a jack in the telephone base and the plug at the other end of the cord in the wall terminal.
Modular plugs for terminating telephone cords are shown, for example, in U.S. Pat. Nos. 3,699,498 and 3,761,869 which issued Oct. 17, 1972 and Sept. 24, 1973, respectively, both in the names of E. C. Hardesty, C. L. Krumreich, A. E. Mulbarger, Jr., and S. W. Walden. Jacks which are adapted to receive modular plugs that terminate new style flat telephone cords are shown for example in U.S. Pat. Nos. 3,850,497 and 3,990,764, the latter two patents being issued on Nov. 26, 1974 and Nov. 9, 1976, respectively.
A jack which is provided in the wall terminal usually includes a single outlet for connecting a station instrument such as, for example, the telephone set to an associated telephone line. However, there are some situations in which it is desirable to be able to connect two station instruments such as, for example, a telephone answering device and an adjacent telephone set in parallel to the associated telephone line at the same location. There are other situations where it may be desirable also to be able to connect an auxiliary power supply to telephone station equipment to provide, for example, power to an incandescent lamp mounted within a telephone set for illuminating a dial or an array of pushbuttons.
An adapter which provides multiple access to a telephone line at a single wall terminal is shown in U.S. Pat. No. 4,241,974 which issued on Oct. 30, 1980 in the name of E. C. Hardesty. The adapter includes a dielectric unipartite housing having a plug end for insertion into a wall terminal and an opposite jack end. Each of a pair of externally communicating cavities at the jack end is adapted to receive a modular plug that is used to terminate a telephone cord and that includes a plurality of spaced, parallel terminals. The plug end which is adapted to be received in a jack cavity of a wall terminal includes a plurality of spaced wire-receiving channels which communicate and which are aligned with spaced wire-receiving channels in each of the cavities at the jack end. A wire-like contact element is mounted in each of the channels of the plug end and has a retroflexed configuration with one free end portion of each contact element extending into the aligned channel in one of the cavities and with the other free end portion extending into the associated aligned channel in the other one of the cavities.
The contact elements must be formed and assembled to the housing in a manner which facilitates high speed production. Considering the geometry of the adapter and its one-piece construction, it should be apparent that the assembly of the contact elements to the housing is a formidable task.
The prior art of forming and assembling wire-like contact elements to a modular connector housing includes commonly assigned application Ser. No. 393,991, filed on June 30, 1982 in the name of E. M. Hutchins and W. M. Schoenemann, Jr. In it, a coupler housing includes opposing cavities and contact elements which extend between the cavities and which have retroflexed end portions in the opposing cavities. The contact elements are formed by feeding a plurality of wires side by side into the housing, forming the wire end portions in one cavity, severing the wires from supplies and then forming the opposite end portions in the other cavity.
Although the prior art includes methods and apparatus for assembling contact elements to a housing having opposed cavities, it seemingly does not include methods and apparatus for assembling contact elements to a housing of the type described for the adapter. Not only are both free end portions of the contact elements at the same end of the adapter housing, but each contact element must be retroflexed at an opposite end of the housing and at each of its end portions.